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Sierra 18-3551 Thermostat for Mercruiser V8 Engines 142°F

Manufacturer

Sierra

<p>For nearly six decades, Sierra has established itself as one of the marine industry's most trusted names in aftermarket engine and drive parts. Founded as a specialized marine parts manufacturer, Sierra has grown into a comprehensive supplier of replacement components, instrumentation, and accessories for both recreational and commercial boating applications. Operating from their 300,000-square-foot distribution center in Litchfield, Illinois, Sierra serves boat owners and marine technicians worldwide with an extensive catalog of parts engineered specifically for the harsh saltwater environment.</p><h3>Marine Engine Excellence</h3><p>Sierra's reputation was built on delivering precision-engineered internal engine components and drive system parts that meet or exceed OEM specifications. Their <a href="/7570-sierra-engine-gasket-set-5404">engine gasket sets</a> provide critical sealing solutions for inboard and outboard motors, while their <a href="/7570-sierra-engine-complete-assembly-15341">engine complete assemblies</a> offer comprehensive replacement options for major overhauls. Each component undergoes rigorous testing to ensure reliability in demanding marine conditions, from corrosion resistance to temperature cycling performance.</p><h3>Instrumentation and Monitoring Systems</h3><p>Accurate instrumentation is essential for boat operators to monitor engine health and prevent costly breakdowns on the water. Sierra's comprehensive line of <a href="/7570-sierra-gauges-200483">gauges</a> includes everything from fuel pressure and temperature indicators to voltmeters and trim gauges, all designed with marine-grade materials that withstand vibration, moisture, and UV exposure. Their <a href="/7570-sierra-tachometer-gauge-1488">tachometer gauges</a> deliver precise RPM readings critical for optimizing engine performance and fuel efficiency. Supporting these instruments, Sierra's <a href="/7570-sierra-gauge-resistor-47908">gauge resistors</a> ensure proper signal conditioning and accurate readings across various sensor types and engine configurations.</p><h3>Expanded Product Portfolio</h3><p>In 2022, Sierra significantly broadened its scope beyond traditional marine engine parts to encompass a wider range of boating accessories and even outdoor power equipment components. This strategic expansion brought established marine brands like Shields and Moeller under the Sierra umbrella, creating a one-stop resource for marine maintenance and replacement parts. The company now offers fuel systems, electrical components, battery charging solutions, and NMEA electronics alongside their traditional engine parts lineup.</p><h3>Quality Backed by Industry-Leading Warranties</h3><p>What sets Sierra apart in the crowded aftermarket marine parts market is their commitment to standing behind every component they manufacture. Their warranty coverage extends beyond simple part replacement—it includes shop labor, haul-out fees, towing charges, and related incidental costs should a warrantied part fail. This comprehensive protection reflects the company's confidence in their manufacturing processes and quality control standards. For boat owners facing repairs far from shore or mechanics working on customer vessels, this peace of mind is invaluable. Whether you're maintaining an outboard motor, rebuilding an inboard engine, or upgrading your boat's instrumentation, Sierra's decades of marine industry experience and commitment to quality make them a reliable choice for keeping your vessel running at peak performance.</p>

Part Number

18-3551
05/28/2036 8:55 PM
Sale Price

$15.81

In Stock (10+)

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Usually delivered within 2 days

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No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-3551 is a precision-engineered replacement thermostat designed for marine applications. This thermostat opens at 142 degrees Fahrenheit, providing optimal engine temperature regulation for reliable performance on the water.

Key Features:

  • 142°F opening temperature for precise cooling system control
  • Direct replacement for OEM Mercruiser thermostats
  • Corrosion-resistant construction for marine environments
  • Engineered to meet or exceed OEM specifications

Compatibility:

  • Fits 1986 and newer V8 Chrysler marine engines equipped with Rochester carburetors
  • Compatible with Ford 302 and 351 cubic inch displacement marine engines

Maintaining proper engine temperature is critical for performance and longevity. This Sierra thermostat ensures your cooling system operates within the correct temperature range, preventing overheating while allowing the engine to reach optimal operating temperature quickly.

Products specifications

Rating: Temperature

142°

Replaces

Mercury 59137, 807252T1 Chrysler 4142885 Crusader 96319 Pleasurecraft R026002E

Good

Wish I could see all the parts with a real representative picture

Easy to find part and verify fit, price is low shipping not outrageous.

great resource for me and my restoration project. Be here shopping again.

Great prices easy to pay with paypal express

A few back and forth pages to get it right

Cheapest I could find anywhere !!!

QUICK AND EASY

Customer Service was excellent. Their online website provided accurate product description and when I called to double check, the gentlemen handled my request with ease and professionalism. Thank you for providing the best pricing on great automotive products. My wife and I purchased a WeatherTech trunk liner that would have cost me over $100 retail price but was able to purchase from Autoplicity for much less!!! Thanks guys and keep up the good work!!

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